The American writer of sharply observed and witty science fiction, Robert Sheckley, has died aged 77 after complications following heart surgery and a stroke. His reputation is founded on the two or three hundred short stories he wrote in a burst of creativity from about 1952, when he was 24. His work was a delight: crisply written, intelligently told, brimming with ideas and threaded with a sense of paranoia that did not take itself too seriously.

Half a century later, the mordant humour and lightly satirical tone of these stories afford a wonderful glancing view of consumerist, status-seeking America, the world of the Saturday Evening Post, Senator Joe McCarthy and the social critic Vance Packard. This was an era when the US emerged from isolationism into an expansive modern state, simultaneously innocent and corrupt.

In a just world, Sheckley would be recognised as one of the most important American short story writers of the 20th century but, as anyone who has read him knows, while justice might in theory be available, it is not for everyone - and then only with a catch. His heroes, innocents abroad, were also ingenious, resourceful, capable of action and always able to utter plain common sense in a galaxy full of conmen, unscrupulous advertisers and inscrutable aliens.

Sheckley began writing science fiction soon after graduating with an arts degree from New York University. He was born in Brooklyn, and had gone straight from high school to the US army, serving during the Korean war. Living in a low-rent apartment in New York, he began pouring out stories but his work was not immediately popular with the fans. In retrospect, he was recognised as an iconic 1950s SF writer, but at the time he was swimming against the mainstream.

He found natural homes in two relatively new magazines, Galaxy and the Magazine of Fantasy & Science Fiction, both with editors interested in broadening the appeal of SF by concentrating on style, wit and storytelling (as opposed to engineering ). That these magazines grew to prominence was at least partly Sheckley's doing, as his stories set a tone that others followed.

Once his stories began appearing in book form - the first was Untouched By Human Hands (1954) - they were regularly reprinted in anthologies, and as collections appeared in Britain and on the continent, the critics took notice.

About this period, Sheckley himself was modest. Although versed in the traditions of SF, and socialising with other writers in the genre, his main influences were from outside. He acknowledged Aldous Huxley, Mark Twain, O Henry and Victor Hugo, and once said that the form his stories took was shaped more by poetry than by other short stories.

The first novel, Immortality, Inc., appeared in 1959 and was filmed in 1993 as Freejack, with Emilio Estevez and Mick Jagger. A string of similar works followed, full of ingenuity, but the essential passivity of the protagonists, who move in a bemused way through upside-down societies, did not work as well in novels as in short stories. Several other works were filmed, most notably A Seventh Victim, made in 1965 as La Decima Vittima (The Tenth Victim) - that was the one where Ursula Andress fired bullets from her bikini top. One of Sheckley's best but least-known novels, The Man in the Water (1961), a Hemingwayesque saga of two men battling it out on a becalmed yacht, was also filmed. The result, Escape from Hell Island (1963), is long forgotten.

A restless man, Sheckley took to travelling from the mid-1960s, living in Mexico, Ibiza, London and Paris before returning to the US in 1980, when, for a couple of years, he was fiction editor of Omni magazine. He was married five times, with a daughter each by his second and third wives. A shambling, stammering man, always genial, endlessly kind, he made friends in every country he visited. He became a close friend of mine in London in the late 1970s, by which time he was bedevilled with writer's block and the distractions of the itinerant life.

One evening we caught part of Douglas Adams' Hitchhiker's Guide on the radio. This was before it was famous. Sheck listened in silence, without a smile. I asked him what he thought of it, and he replied: "He writes good jokes." He didn't add what seemed obvious to me, that most had originally been his.